title: Calix[n]arene carboxylic acid derivatives as regulators of enzymatic reactions: enhanced enantioselectivity in lipase-catalyzed hydrolysis of (R/S)-naproxen methyl ester.
abstract: Candida rugosa lipase was immobilized with a sol-gel encapsulation procedure in the presence and absence of a calix[n]arene carboxylic acid derivative grafted onto magnetic nanoparticles or in the presence of the calix[n]arene carboxylic acid derivative with Fe3O4 magnetic nanoparticles as an additive. Through the enantioselective hydrolysis of racemic naproxen methyl ester and the hydrolysis of p-nitrophenylpalmitate, the relative enzyme activity was evaluated and tested. These results show that the encapsulated lipase without supports has lower conversion and enantioselectivity compared to the Calix[n]COOH-based encapsulated lipase. It has also been observed that the Calix[4]COOH-based encapsulated lipase has excellent enantioselectivity (enantiomeric ratio (E) > 400) as compared to encapsulated-free lipase enantioselectivity (E = 137), and it also has an enantiomeric excess value of ~98 % for S-naproxen.
authors.affiliation: Department of Chemistry, Selcuk University, 42031, Konya, Turkey.
authors.forename: Enise
authors.initials: E
authors.lastname: Akoz
authors.forename: Osman Y
authors.initials: OY
authors.lastname: Akbulut
authors.forename: Mustafa
authors.initials: M
authors.lastname: Yilmaz
mesh_terms: D055162:Biocatalysis / Q000187:drug effects*; D047250:Calixarenes / Q000737:chemistry / Q000494:pharmacology*; D002175:Candida / Q000201:enzymology*; D002264:Carboxylic Acids / Q000737:chemistry*; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis / Q000187:drug effects; D008049:Lipase / Q000737:chemistry / Q000378:metabolism*; D058185:Magnetite Nanoparticles / Q000737:chemistry; D009288:Naproxen / Q000737:chemistry* / Q000378:metabolism*; D012821:Silanes / Q000737:chemistry; D013237:Stereoisomerism; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D002264:Carboxylic Acids; D004800:Enzymes, Immobilized; D058185:Magnetite Nanoparticles; D012821:Silanes; D047250:Calixarenes; D009288:Naproxen; D008049:Lipase